| Official Name: | Oak Grove Township |
| Settlement Type: | Township |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Indiana |
| Subdivision Type2: | County |
| Subdivision Name2: | Benton |
| Government Type: | Indiana township |
| Established Title: | Organized |
| Established Date: | July 1840 |
| Area Total Sq Mi: | 35.53 |
| Area Land Sq Mi: | 35.51 |
| Area Water Sq Mi: | 0.02 |
| Population As Of: | 2020 |
| Population Total: | 1551 |
| Population Density Sq Mi: | 43.6 |
| Timezone: | EST |
| Utc Offset: | -5 |
| Timezone Dst: | EDT |
| Utc Offset Dst: | -4 |
| Elevation Footnotes: | [1] |
| Elevation M: | 228 |
| Elevation Ft: | 748 |
| Coordinates: | 40.5192°N -87.265°W |
| Blank Name: | FIPS code |
| Blank Info: | 18-55620[2] |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 453681 |
Oak Grove Township is one of eleven townships in Benton County, Indiana. As of the 2020 census, its population was 1,551 and it contained 690 housing units.[3] It was one of the first three townships originally created by the county's commissioners in 1840.[4] It takes its name from White Oak Grove which grew southwest of Oxford.[5]
According to the 2020 census, the township has a total area of, of which (or 99.94%) is land and (or 0.06%) is water.[3]
The township contains two cemeteries: Justus and Oxford.